In a typical cellular radio system, mobile stations (MSs), also referred to as user equipment nodes (UEs) and/or wireless terminals, communicate via a radio access network (RAN) with one or more core networks. The RAN covers a geographical area which is divided into cell areas, with each cell area being served by a base station subsystem (BSS), which is also referred to as a radio base station, base station, RAN node, a “NodeB”, and/or enhanced NodeB “eNodeB. A cell area is a geographical area where radio coverage is provided by the BSS equipment at a BSS site. A BSS communicates through wireless radio communication channels with MSs within range of the BSS.
A MS communicating with a BSS transmits an access request over a random access channel when the MS has data for transmission to the BSS, and responsive to the access request, the BSS transmits an assignment message identifying uplink resources that have been allocated for the MS uplink data transmission(s).
All MSs must have a valid Timing Advance (TA) value in order to be allowed to transmit radio blocks on the assigned uplink resources to the network. The 3GPP TS 44.060 specification states that “Initial timing advance may be provided in the PACKET UPLINK ASSIGNMENT in the TIMING_ADVANCE_VALUE field”. The 3GPP TS 44.018 specification states that the Immediate Assignment message includes a mandatory “Timing Advance” Information Element, IE, which provides initial timing advance information to a MS.
Thereafter, either the timing advance is updated with a PACKET POWER CONTROL/TIMING ADVANCE message or a continuous timing advance procedure is used. If a Timing Advance Index is included in the assignment message, the MS shall use the continuous timing advance procedure, using its allocation on Packet Timing advance Control Channel, PTCCH, (see 3GPP TS 45.010).
A MS is not allowed to send normal bursts on the uplink of an assigned radio resource unless it periodically receives valid TA values in a dedicated message (i.e. sent individually to each MSs) consisting of the 3GPP TS 44.060 PACKET POWER CONTROL/TIMING ADVANCE message.
As the number of mobile stations admitted to utilize a given set of radio resources is increased, the process for periodically sending dedicated 3GPP TS 44.060 PACKET POWER CONTROL/TIMING ADVANCE messages will result in increased radio resource consumption in support of the control plane communications. Consequently, the amount of radio resources that are available for user plane transfers will decrease and overall radio resource utilization efficiency will similarly decrease.